Merge pull request #1838 from marco-c/boehm_heuristics

Use Boehm's GC heuristics instead of our own

Makefile

@@ -86,7 +86,7 @@ else
 endif
 
 ifeq ($(RELEASE),1)
-	CLOSURE_FLAGS = 
+	CLOSURE_FLAGS =
 else
 	CLOSURE_FLAGS = --formatting PRETTY_PRINT
 endif
@@ -340,7 +340,7 @@ bld/native.js: Makefile vm/native/native.cpp vm/native/Boehm.js/.libs/$(BOEHM_LI
 	emcc -DNDEBUG -Ivm/native/Boehm.js/include/ vm/native/Boehm.js/.libs/$(BOEHM_LIB) -Oz -O3 \
 	vm/native/native.cpp jit/relooper/Relooper.cpp -o native.raw.js --memory-init-file 0 \
 	-s TOTAL_STACK=16*1024 -s TOTAL_MEMORY=$(ASMJS_TOTAL_MEMORY) -DGC_INITIAL_HEAP_SIZE=$(GC_INITIAL_HEAP_SIZE) \
-	-s 'EXPORTED_FUNCTIONS=["_main", "_lAdd", "_lNeg", "_lSub", "_lShl", "_lShr", "_lUshr", "_lMul", "_lDiv", "_lRem", "_lCmp", "_gcMallocUncollectable", "_gcFree", "_gcMalloc", "_gcMallocAtomic", "_gcRegisterDisappearingLink", "_gcUnregisterDisappearingLink", "_registerFinalizer", "_forceCollection", "_getUsedHeapSize", "_rl_set_output_buffer","_rl_make_output_buffer","_rl_new_block","_rl_set_block_code","_rl_delete_block","_rl_block_add_branch_to","_rl_new_relooper","_rl_delete_relooper","_rl_relooper_add_block","_rl_relooper_calculate","_rl_relooper_render", "_rl_set_asm_js_mode"]' \
+	-s 'EXPORTED_FUNCTIONS=["_main", "_lAdd", "_lNeg", "_lSub", "_lShl", "_lShr", "_lUshr", "_lMul", "_lDiv", "_lRem", "_lCmp", "_gcMallocUncollectable", "_gcFree", "_gcMalloc", "_gcMallocAtomic", "_gcRegisterDisappearingLink", "_gcUnregisterDisappearingLink", "_registerFinalizer", "_forceCollection", "_collectALittle", "_getUsedHeapSize", "_rl_set_output_buffer","_rl_make_output_buffer","_rl_new_block","_rl_set_block_code","_rl_delete_block","_rl_block_add_branch_to","_rl_new_relooper","_rl_delete_relooper","_rl_relooper_add_block","_rl_relooper_calculate","_rl_relooper_render", "_rl_set_asm_js_mode"]' \
 	-s 'DEFAULT_LIBRARY_FUNCS_TO_INCLUDE=["memcpy", "memset", "malloc", "free", "puts"]' \
 	-s NO_EXIT_RUNTIME=1 -s NO_BROWSER=1 -s NO_FILESYSTEM=1 --post-js jit/relooper/glue.js
 	echo "var RELOOPER_BUFFER_SIZE = 1024 * 512;" > bld/native.js

int.ts

@@ -623,9 +623,7 @@ module J2ME {
       // we consistently stay in compiled code. Most code unwinds often enough that we can
       // force collection here since at the end of an unwind all frames are
       // stored back on the heap.
-      if (getFreeMemory() < Constants.FREE_MEMORY_TARGET) {
-        ASM._forceCollection();
-      }
+      ASM._collectALittle();
     }
 
     /**

vm/native/native.cpp

@@ -131,6 +131,10 @@ extern "C" {
     GC_gcollect();
   }
 
+  void collectALittle(void) {
+    GC_collect_a_little();
+  }
+
   int getUsedHeapSize(void) {
     GC_word heapSize;
     GC_word freeBytes;

vm/runtime.ts

@@ -405,7 +405,7 @@ module J2ME {
       this._runtimeId = RuntimeTemplate._nextRuntimeId++;
       this._nextHashCode = (this._runtimeId << 24) | 1; // Increase by one so the first hashcode isn't zero.
     }
-    
+
     preInitializeClasses(ctx: Context) {
       var prevCtx = $ ? $.ctx : null;
       var preInit = CLASSES.preInitializedClasses;
@@ -666,15 +666,6 @@ module J2ME {
     TWO_PWR_32_DBL = 4294967296,
     TWO_PWR_63_DBL = 9223372036854776000,
 
-    // The target amount of free memory (in bytes) before garbage collection is forced on unwind.
-    // Note: This number was chosen through ad-hoc testing of a midlet, which showed
-    // that the midlet OOMed once less than ~3MB of memory was available, presumably
-    // because compiled codeis allocating more than that before unwinding.  It would be
-    // useful to have more insight into which code allocates memory, and in what chunks,
-    // so we can set this to the maximum amount of memory needed by compiled code.
-    // But this value seems to work ok in the meantime.
-    FREE_MEMORY_TARGET = 4 * 1024 * 1024, // 4MiB
-
     // The size in bytes of the header in the memory allocated to the object.
     OBJ_HDR_SIZE = 8,